Nature of Memory

Sensory Memory- holds relatively unprocessed information for a few seconds after stimulus.

Short Term Memory- stores information for a brief period of time.

STM has a limited capacity of 7+-2, Jacobs (1887). P's given a sequence of digits which they had to repeat. Found P's could remember five and nine items on one exposure.

STM has a brief duration of 15-30 seconds, Peterson & Peterson (1959). P's given trigrams to be recalled after delay of 3,6,9,15 or 18 seconds. In between given an interference task of counting back in threes (preventing rehearsal). Found longer the time delay, more forgetting- by 18 secs, 10% were remembered. Shows information is lost rapidly (18 secs) if there is no repetition of material.

Encoding in the STM is usually acoustic Baddeley (1966). P's given acoustically dis/similar words and semantically dis/similar words to learn. In ST had to recall immediately, in LT after 20 min interference task. ST most accurate with acoustically dissimilar, LT with semantically dissimilar. Shows ST encoded acoustically, LT encodes semantically.

Long Term Memory- holds vasts amount of information for long periods of time.

Capacity of LTM is unlimited.

Duration of LTM is potentially a whole life time. Bahrick (VLTM).

Encoding is semantic in LTM, proposed by Baddeley (1966).

Multi Store Model (Atkinson & Shiffrin 1968)

Consists of 3 unitary stores: sensory/ short/ long term. Information goes in a linear flow. From environment to sensory store where if attended processed to STM, if not decay and lost. STM encoded acoustically, limited capacity so rehearsed and passed on to LTM or lost by 30 secs. Once in LTM, encoded semantically and permenent.

Shallice & Wsrrington (1970) studied KF who had brain damage after bike accident. His STM was impaired but LTM fine. Supports MSM and distinction in stores.

+Brain Scans highlight different areas of the brain during tasks supporting different stores.

Shepard & Feng (1972). P's has to imagine folding a cube to decide whether arrows met. Time taken related to number of folds in cube showing we manipulate images in STM. Reflects everyday life and multi tasking.

-Parts of the model are unclear, eg how the central executive interacts with other stores. - Doesn't look at links with long term memory. - Does not take account for the senses.

Cognitive Interview (Geiselman et al 1985)

1. Cognitive Reinstatement (CR)- recall context of the event eg. weather, feelings 2. Report Everything- even if it seems trivial 3, Recall From Changed perspective (CP)- describe the event from different viewpoints 4. Recall In Reverse Order- report in different time orders.

+ Trivial details help trigger LTM of central events. + Elicits the most information. + CR and RE are easy and more effective than CP and RO.

Eye Witness Testimony

Invtestigates the accuracy of memory following an accident, crime etc.

Mnemonics- rely on effective retrieval cues and encoding in unique ways. Eg- Loci, latin for 'places' converts each item to image and mentally places in location.

Tulying & Thompson support this stating Encoding Specificity Principle (ESP) where we learn with links to context, acting as retrieval cues. It also allows elaborate rehearsal leading to stronger memory trace..